Solutions for renewable energy systems

Converting solar energy into electricity is one of the most significant advancements in modern technology. Solar energy, as a clean and renewable source, plays a vital role in reducing carbon emissions associated with traditional energy consumption. By 2050, solar power is expected to contribute up to 25% of global electricity, helping mitigate the effects of climate change.

At LEM, we are committed to advancing solar energy through high-tech sensors and solutions, ensuring solar inverters and related systems operate more efficiently, reliably, and affordably.

Solar inverters are essential components in converting DC power generated by renewable energy sources, like solar panels and wind turbines, into AC power that can be used in homes, businesses, or the electrical grid. Current Sensor ICs in these inverters monitor electricity flow to ensure the output current meets safety standards and system requirements.

When selecting an inverter, factors such as system size, grid connectivity, energy storage, and performance objectives play a crucial role.

Types of Solar Inverters

String Inverters vs Centralized Inverters

There are two main types of photovoltaic (PV) systems used today:

• String Inverters: Designed for small to medium power systems.
• Centralized Inverters: Used for larger, utility-scale power systems.

Micro Inverters

Micro inverters are compact devices installed directly onto individual solar panels. Unlike traditional string inverters, which connect multiple panels in series, each micro inverter converts DC electricity from its respective panel into AC electricity independently. This approach can enhance system performance by isolating the output of each panel, making it more efficient and reducing the impact of shading or panel failures.

String inverter 

String inverters connect to a series of solar panels (PV strings) and are typically installed in a central location. They are ideal for medium to large-scale solar installations and can deliver power to a single-phase or three-phase grid, with capacities ranging from a few kilowatts to hundreds of kilowatts.

Key features of string inverters include:

• High protection grade (often IP65)
• No need for a combiner box
• Wide input DC voltage range
• Advanced MPPT (Maximum Power Point Tracking) control
• High efficiency
• Flexible configurations for various applications

String inverters are cost-effective solutions commonly used in grid-tied solar PV systems, installed either indoors or outdoors, and can serve both residential and commercial applications.

Centralized inverter

Centralized inverters convert DC electricity from multiple solar panels or wind turbines into AC electricity at a single power stage. They are typically used in large-scale systems, such as utility-scale solar farms or commercial rooftop installations, with capacities often exceeding 500kW per unit.

Centralized inverters are ideal for large power stations due to their ability to handle significant power outputs and deliver high efficiency.

Key features of centralized inverters include:

• Easy maintenance and energy management
• High power density with low costs
• Enhanced security for large installations
• Power factor adjustment and low voltage ride-through capability

Centralized inverters are commonly installed at central points within large solar farms or wind energy systems to streamline power conversion and transmission to the grid.